1. Field of the Invention
The present invention relates to an electronic apparatus and a method of manufacturing the electronic apparatus, and more particularly to an electronic apparatus where a circuit chip is mounted on a base sheet and a method of manufacturing the electronic apparatus.
2. Description of Related Art
Conventionally, electronic apparatus have been widely known where a circuit chip is mounted on a substrate, such as a printed circuit board (“PCB”). Such an electronic apparatus is embedded into an electronic device and mainly used to control the electronic device or exchange information with an external device as a unit. As an example of the electronic apparatus, various types of RFID (Radio Frequency Identification) tags are known, which contactlessly and wirelessly exchange information with an external device represented by a readers/writer. As an example of such RFID tags, an RFID tag including an IC (Integrated Circuit) chip and an antenna pattern mounted on a base sheet, which is a conductive pattern for wireless communication and serves as an antenna, has been proposed (for example, see Japanese Patent Application Publication Nos. 2000-311226, 2000-200332, and 2001-351082). This type of RFID tag is used, for example, to perform identification of a product by exchanging information associated with the product with an external device, while being attached to the product.
One of applications for such an RFID tag is that the RFID tag is attached to a product, such as a garment, which may be subjected to deformation during use. In this application, a bending stress exerted on the RFID tag may cause the antenna pattern to be disconnected, which may lead to a failure of functions as an antenna.
FIG. 1 is a cross sectional view illustrating a conventional RFID tag 10′ which has been bent due to a bending stress.
The conventional RFID tag 10′ includes a base sheet 111 made of a PET film, a conductive antenna pattern 112 for communication arranged on the base sheet 111, and a circuit chip 12 connected to the antenna pattern 112. The base sheet 111, the antenna pattern 112, and the circuit chip 12 are coated with a rubber coat article 100a. If a bending stress is exerted on the conventional RFID tag 10′ in the direction of an arrow shown in FIG. 1, the conventional RFID tag 10′ is subject to a bending deformation in this direction following the bending stress. At this time, a large bending stress, which would separate the antenna pattern 112 into two parts, is exerted on an area A′ where bending deformation greatly takes place, and therefore, disconnection of the antenna pattern 112 may easily occur in the area A′. This bending stress becomes stronger as the bending angle of the RFID tag 10′ increases. Accordingly, the RFID tag 10′ that can be excessively bent is liable to be easily disconnected, and thus becomes poor in durability.
Although the above descriptions refer to the case where the conductive pattern serving as an antenna is disconnected, such disconnection of the conductive pattern is not limited only to the RFID tag, but common to all electronic apparatus whose conductive pattern is mounted on the base sheet.